Cloudformation 模板中的组合 Fn::Select + Fn::Split + Fn:GetAtt

Question

I'm trying to use the following cloudformation stack but i keep failing with the following error:

Template error: every Fn::Split object requires two parameters, (1) a string delimiter and (2) a string to be split or a function that returns a string to be split.

  {
      "Type": "AWS::Route53Resolver::ResolverRule",
      "Properties": {
        "DomainName": {"Fn::Sub": "ad.${EnvName}.yyy.xxx.com"},
        "Name": {"Fn::Sub": "${EnvName}"},
        "ResolverEndpointId": "1",
        "RuleType": "FORWARD",
        "Tags" : [
          {
            "Key": "Name",
            "Value": {
              "Fn::Sub": "${EnvName}-ADResolverRule"
            }
          }
        ],
        "TargetIps": [
            {
                "Ip": {
                    "Fn::Select": [
                        0,
                        {
                            "Fn::Split": [
                                ",",
                                {
                                  "Fn::GetAtt": [
                                      "MicrosoftAD",
                                      "DnsIpAddresses"
                                  ]
                                }
                            ]
                        }
                    ]
                },
                "Port": "53"
            }
        ]
      }
    }

not really sure why as i have values for the Fn::Split function, any help would be appreciated.

Thanks.

Answer 1

The issue looks to be that you do not need to call split at here. When you call Fn::GetAtt, it is not creating a string in this case. If you look at the documentation , it generating a list object. Looking at various examples you'll see the split is not necessary.